The present invention relates to immobilizer systems for installation in vehicles, immobilizer operation members incorporating immobilizer transmitters for transmitting immobilizer identification codes, and immobilizer operation member receiving devices for receiving the immobilizer operation members.
Automobile engines are started by inserting an ignition key into a key cylinder and turning it.
In recent years, to prevent thefts, ignition keys that control engine starting with electric signals, which are transmitted from the key, in addition to key turning have been used.
Such an ignition key incorporates a transmitter that transmits a special identification code (immobilizer identification code). When the identification code transmitted from the transmitter matches an identification code preset in an engine starting control computer (i.e., ECU) of a receiver installed in the vehicle, the engine is electronically controlled and started. Therefore, the starting of the engine is permitted only by a key incorporating the transmitter. This prevents the automobile from being stolen. Such a system is referred to as an immobilzer system.
The transmitter, which is incorporated in the ignition key, is driven by a battery, which is located in the grip of the key, to transmit an identification code when a switch located on the grip is operated. However, the identification code cannot be transmitted when the battery becomes low on power. In such case, the engine cannot be started even when using an authorized ignition key. Thus, ignition keys incorporating immobilizer transmitters (hereafter referred to as transponders) that do not require batteries have recently become popular.
When magnetism produced by a magnetism generator of the receiver reaches the transponder, the transponder converts the magnetic energy to electric energy to generate electric power. The electric power is used to transmit the radio waves of the identification code. This eliminates the need to replace batteries and enables usage over a long period of time.
Generally, if a duplicate of the ignition key incorporating the immobilizer transmitter is necessary, the duplicate must be bought from the dealer who sold the automobile.
However, in the prior art, the surface of the ignition key only includes markings such as the trademark of the automobile maker. Thus, if the user forgets that the ignition key incorporates an immobilizer transmitter, the user may have a locksmith produce a duplicate that only copies the shape of the ignition key plate.
Although such a duplicate key has a key plate that is identical to that of the ignition key, the duplicate key does not incorporate the immobilizer transmitter. Accordingly, if the duplicate key is inserted into the key cylinder and turned to start the engine, the engine will not start. Furthermore, if a number of people use the same ignition key, some of them may not know about the immobilizer system. In such case, the ignition key may be handled carelessly, in the same manner as a normal ignition key that does not incorporate an immobilizer transmitter.
Additionally, in this system, it may be difficult to determine whether there is a problem with the vehicle or the immobilizer transmitter in the ignition key when the engine does not start. In the prior art, there is no way to recognize that the ignition key is one element of the immobilizer system. Thus, if efforts to locate the cause of the problem are directed only toward the vehicle, troubleshooting of the ignition key will be delayed.